B.C. is usually set in a traditional, relatively arid “prehistoric” landscape. Lots of rocks, cliffs, mountains, and caves, just like we all associate with “stone age” society. Trees do occur in the strip (the Midnight Skulker uses one for his costume changes), but forests are almost never seen. The reason is simple: it is much easier to draw a barren wasteland than a lush woodland.

Johnny Hart’s style was particularly sparse, his was a minimalist approach to comic strip design, with backgrounds that often consisted of just a line or two to suggest plains, hills, caves, etc. I can’t recall off the top of my head any time when he drew a “forest”, although, as noted above, the Midnight Skulker changes in a “phone booth” that’s made out of a tree, and sometimes there might have been enough trees around to constitute a “grove”… but forests are complicated things, with a variety of both plants and animals existing at several distinct levels.

Oh, I get it now. It’s like the Peanuts comic strip where Charlie Brown and Lucy are listening to a record of “Old Rocking Chair Got Me”, and Lucy asks “What’s a rocking chair?” and we see the entire living room full of moderne furniture.